Many photocopiers, printers, and other reproduction and printing devices now include non-volatile memory (NVM), such as magnetic and optical storage media and including removable disk systems, hard drives, and other storage media systems allowing the device and/or a user to store a job the device uses or is directed to use the stored job. In high security areas (e.g., military installations), there is often a requirement that all jobs that stored on NVM of a device shall be inaccessible once the job is completed. Additionally, users in lower security area often wish to erase data they would like to keep private or confidential for various reasons.
A risk to security arises when a printing device loses power while printing, processing, or storing incomplete pending jobs in a queue. When the device regains power, it will typically check for incomplete and/or pending jobs and print them. If the loss of power lasts too long, the user may leave the vicinity of the printing device and the output of the device can remain in an output tray for a long time, possibly forgotten by the user who sent the job or simply languishing because the user has gone home for the day.
Embodiments address this problem by introducing a method and apparatus that checks the duration of the power loss against a reference duration and erasing any pending and/or incomplete jobs when power is restored, rather than printing the jobs and leaving them vulnerable. Notices can be sent to the users who sent the job(s) so that they know what happened to the jobs. The duration can be checked by using a chronometer, accessing an on-board clock of the device, checking a device log, or a combination or two or more of these. The reference duration can be preprogrammed or user defined. Preferably, the erasure is accomplished using a secure erase routine.
Lately, secure erase systems that overwrite the data with patterns of 1s, 0s, or random combinations thereof have come into use to meet erasure requirements. However, government agencies and other customers have different requirements as to how many times one can overwrite the appropriate portions of NVM once a job or task is completed, which can lead to difficulties in product design and implementation.
Embodiments of the invention allow a user or a system administrator (SA) to program a device to overwrite the region of NVM in which the data file associated with a print, scan, fax, copy, or other job resides. In embodiments, the data file is overwritten more than once, such as from 2 to about 50 times, with the exact number of overwrites being determined according to a stored default value or a user-input value. Further, in embodiments, the data file can be overwritten with a different pattern on each overwrite according to a stored default value or a user-input value. For example, if a user has just printed something stored on a floppy disk, the user can erase it securely with a sequence of patterns of choice. Instead of trying to settle on a single algorithm (e.g., overwrite 3 times, first time with 1s, the second time with 0s, the third time with a random pattern), this allows overwriting “n” times with a set of patterns that can be downloaded to the device.
Embodiments activate an erase trigger automatically, which places the digital copier or printer into, for example, an Image Disk Erasing Routine, where an Image Disk is a storage media used by the device to store data files including scanned images of documents and/or print job data and the like. An example of such an Erasing Routine is a routine that executes three complete erasures with a check to ensure the data is completely erased; per industry or security approved processes. The Erasing Routine removes or destroys any residual data files including documents, images, and the like, on the Image or ESS Disks. In embodiments, a customer selectable UI/client button with confirmation that the process was completed could activate this routine. During this erasing feature, the system would be offline.
Thus, a feature of the invention provides a storage medium security erase system comprising an erase trigger that tells a drive sector analyzer to retrieve data file location information from a CPU and send the location information to a secure storage medium eraser that overwrites the data file according to a predetermined secure erase method, the eraser using a type of overwrite pattern and a number of overwrites determined by an erase pattern determiner according to predetermined criteria and/or user input.
An additional feature of the invention is to apply a method of securely erasing a data file by a providing an erase trigger, determining a location of the data file on the storage medium, overwriting the data file according to a predetermined secure erase method, and determining at least a number of times to overwrite the data file in response to the erase trigger and according to predetermined criteria.
Advantageously, embodiments determine how long a power loss has lasted and invoke an erase routine, such as a secure erase routine, when the power loss exceeds a threshold duration.